The invention relates to a method for repairing the electric insulation layers between the sheet metal pieces of sheet metal segments of electric generators and motors, wherein between two neighboring sheet metal pieces an electric insulator is arranged, respectively.
The present invention is designed for electric generators as well as electric motors for industrial applications. Such electric generators as well as electric motors are comprised of sheet metal segments of stacked sheet metal pieces. Thin electric insulation layers are arranged between the individual pairs of sheet metal pieces. The problem of these electric generators and motors resides in that, for example, as a result of aging or vibrations, loosening can occur, in particular, loosening of the windings within the sheet metal segment, on the one hand, and loosening of the sheet metal pieces, on the other hand. The result of loosening of the sheet metal pieces is that the interposed insulation layers are subjected to wear. Because of this, short circuits can result which lead to heat generation and can cause core burning in extreme situations.
The repair of worn electric insulation layers between the sheet metal pieces of sheet metal segments of electric generators has been performed in the past in that by means of a so-called beveled-edge chisel the intermediate space between two sheet metal pieces is widened. Subsequently, a mica platelet is inserted into the intermediate space. Mica is an electric insulation body. The inserted mica platelet repairs the defective insulation between the two neighboring sheet metal pieces. Alternatively, coatings of insulation varnish or resin are applied by means of a brush or by drip impregnation.
The disadvantage of these known repair techniques resides in that the new insulation does not penetrate deeply into the sheet metal segment so that defects of the insulation layers that are positioned deep within the sheet metal segment cannot be repaired.